Grate frame construction



June 6, 1933. J 5 THOMPSON 1,912,868

GRATE FRAME CONSTRUCTION Filed Feb. 25, 1930 \34 J4 ATTORNEYS Patented June 6, 1933 y UNITED STATES PATENT ounce JAMES S..THO1VIPSON, OF NEW ROCHELLE, NEW YORK, ASSIGNOR TO FIREBAR CORPO- RATION, OF CLEVELAND, OHIO, A CORPORATION OF DELAWARE G-BATE FRAME consrauorron Application filed February 25, 1930. Serial No. 431,285.

This invention relates to grates of the type used in locomotives,marine boiler furnaces and for other similar heavy duty purposes. More specifically, the invention is concerned with a rate construction, which consists of a grate frame and grate barssupported therein, the frame being so formed that fuel supported on it is properly consumed,

In my co-pending application, Serial No. 431,282 filed February 25, 1931, I have set forth the difficulties involved in the burning of fuel on grates as at present constructed and have shownthat these difficulties arise from-the failure of grate builders to appreciate that the top of the grate frame serves as fuel-supporting surface and that air should be supplied to the fuel carried on the frame as well as to the fuel supported on the grate bars. Since in present grates the top of the grate frame is solid and represents dead area through which no air is supplied and the total. area of the top. of the frame may be as much as per cent of the total cross-sectional area of the fire box, it will be apparent that so large a proportion of dead area beneath the fuel bed seriously interferes with the combustion of the fuel and greatly reduces the combustion efliciencyl In the co-pending application, I have described a grate construction in which these difficulties are overcome and in that construe tion, the grate frame is providedwith fuelsupporting units which include means for supplying air to fuel supported thereon. By this arrangement, the dead area throughout out with proper support of the fuel.

The grate construction of the present invention affords substantially the same advan tages as those made available by the grate of the co pending application, but the present construction differs from the other in numerous respects and represents an alternative means for obtaining the advantages above pointed out. a p i In the. present grate, the grate frame is providedwith a plurality of fuel-supporting units which are removable from the main frame castingso that they can be separately installed and readily replaced if they become 0 burned or otherwise injured. Each of these the fire box is reduced to a minimum consistfuel-supporting units is provided, with a depression which constitutes a socket for receiving the trunnion of a grate bar. I prefer to use bars of the type disclosed in the Bucle ley application Serial No. 388,352,fi1ed February 8, 1929, now Patent No. 1,884,557, Oct. 25, 1932, by reason of the improved combustion obtained with such bars, although bars of spandard construction may be used if de- S1l6C.. I

The Buckley bar consists ofa carrier member and a plurality of cross-bars mounted thereon i and readily detachable therefrom. The fuel-supporting unit having the trunnion sockets in which the trunnions of the bar are mounted has a shape quite similar to that of the cross-bars of the Buckley construction, and this unit is provided with means by which air is sl'lpplied to fuel supported thereon. r

For the better ululerstanding of the in vent-ion, reference may be. had to the accompanying drawing, in which Fig. 1 isa view in side elevation'of a part of the new grate;

Fig. 2 is a fragmentary plan view of the grate; a t

Fig. 8 is a view in side elevation of a part of the invention on an enlarged scale;

Fig. 4 is a sectional View on the line 4llof Fig. 3;

Fig. 5 is a plan view of certain parts shown in Fig. 4:; and

Fig. 6 is a plan view of a sidegrate frame.

Referring now to the drawing, the new grate comprises a pair of side frame members, only one of which is shown designated 10, a center frame member 11, and a plurality of grate bars 12 which extend cross-wise of the frame members and are mounted at their ends therein. In some fire boxes there are two side frame members and a single frame member along the middle of the fire box, while in others, there may be two cen ter frame members. In either arrangement, the grate bars are in groups and the bars of each group are connected to a common shakerrod so that they may be rocked in unison in the usual manner.

Grate bars of standard construction providcd with trunnions 13 at their ends may be used in the new grate, but I prefer to use grates of the Buckley type. The Buckley grates include a carrier member 14 and a plurality of fuel-supporting cross-bars 15 mounted on the carrier member and individually removable therefrom. The carrier member is provided with trunnions 13.

The grate frame members include a web 16 extending from end to end of the fire box and provided with means 17 at its ends by which the frame member is mounted on supports 18. The web 16 is strengthened by a bottom flange 19 and at its top may have a similar flange 20. If desired, the frame may have a straight top as indicated in Fig. 1, in which event, the web has a variable width with its greatest width at the point 21 adjacent the middle of the frame, the bottom sloping up- 20 Ward from this point toward each end of the grate. Instead of this arrangement, the frame member may have a straight bottom edge and be provided with upward extensions 22 at spaced points from end to end.

Mounted in a row lengthwise of the frame member are upstanding lugs 23 and on these lugs are mounted fuel-supporting units 24. Each fuel-supporting unit consists of a web 25 provided with a recess 26 in its lower edge in which the lug 23 may be received. Near the top of the web and on opposite faces thereof are lugs 27 lying spaced apart in a row from one end of the plate to the other. These lugs extend downward from the top of the plate and they are of decreasing width from the top downward so that passages 28 are formed between them for the upward flow of air. At its upper end each lug terminates in a projection 29, the top of which is sub-divided by intersecting air channels 30 to form small fuel-supporting surfaces 31. In the construction illustrated, there are four such surfaces 31 at the top of each projection 39 and the intersecting air channels 30 which separate the fuel-supporting surfaces communicate at their ends with the passages 28 or with a passage 31 which extends along the top of the plate between projections on opposite sides. With this arrangement, air which flows up through the passages to the channels, flows around the sides of each of the minor projections, the tops of which constitute the fuel-supporting surfaces and these minor projections are thus kept cool, and a wide dis tribution of air is obtained.

In the middle of the top of each fuel-supporting unit there is formed a recess or socket 32 preferably defined by a strengthening rib 33 and this socket is arranged to receive a trunnion 13 of the grate bar. If desired, the plate may be strengthened below the socket by a projection 33 leading down to the top of the recess 26. A

In assembling the new grate, the side and center frame members are first placed in position and thereafter the fuel-supporting units are, mounted on the lugs 23. These units may be secured against accidental displacement therefrom oil the ends of the lugs in any desired manner, such as by providing extension lugs 34 from the ends of the lugs, the extensions overlying the faces of the fuelsupporting units to a slight extent. The grate bars are then placed with their trunnions in the sockets in the fuel-supporting units, and the shaker arms of the grates connected to the usual shaker rod. It will be seen that the lug 23 consists of a web 35 lying substantially horizontal and a flange 36 extending upwardly along the middle of the web. The recesses 26 of the fuel-supporting units have a shape closely similar to the contour of the lugs 23 and these units rest on inclined surfaces 37 at the top of the web 35. At the opening to the recess 26, the plate 25 is provided with lugs 33 on opposite sides thereof and the distance between the lugs 38 is but slightly in excess of the length of the web 35. With this arrangement, when the grates are shaken, there is no possibility of the fuel-supporting units being dislod ed from the lugs since any lateral movement of a unit on its lug immediately brings one or the other of the lugs 38 into locking position below the end of the flange 35 and the extension lugs 34 atthe ends of the main supporting lugs 35 prevent the units from being dislodged off the ends of the lugs.

There is a single fuel-supporting unit on each lug on the side frame member 10, while on the center frame members which are substantialiy wider than the side frame members, each lug carries a pair of units 24 as shown more clearly in Fig. 4. These units rest side by side on the lug and each one supports the trunnion of a single grate bar. In order to keep the units properly spaced at the top, certain of the lugs 27 are provided with spacing projections 39 and when the units are placed on a single lug of the center frame, the spacing lugs on their opposed faces lie in contact so as toimaintain the units at the proper spacin In the new grate, the fuel on the grate bars receives air from the ash pan in the ordinary manner and air may also flow up around the frame and up through the passages 28 to fuel carried on the top of the fuel-supporting units. In the ordinary frame, the top is flat and there is no means of access for the air to fuel carried thereby. As a consequence, this fuel burns sluggishly, the combustion is imperfect, there is a loss of fuel and frequent formation of clinkers. IVit-h the present frame, the fuel carried on the units of the frame receives air quite as effectively as fuel carried on the grate bars and therefore the live area of the grate is increased by the area of the top of the frame itself.

i with the uel bed are removable, it will be Also, in the new frame, the main frame member is much lighter in weight than frames as at present constructed and since those parts of the frame, namely the fuelsupportin units, which come into contact apparent that there is little likelihood of the frame being injured in use and should one or more of the units become burned, the injured parts can be removed and replaced with little difiiculty and with only a small loss of metal. The lugson the top of the frame are spaced so that the tops of a pair of adjacent units lie sufficiently close together so that fuelcannot fall between them upon the framex These units may be dropped in place without trouble and when n position they cannot be accidentally dislodged by reason of the locking parts provided for the purpose. 7

What I claim:

1. A grate comprisin the combination of a frame, a plurality of uel-supporting units mounted on said frame for limited rocking movement in a plane parallel to the longitudinal axis of said frame, and grate bars supported at their ends by said un ts. V 2. A grate comprising the combination of a frame, a plurality of fuel-supporting units mounted on the top of said frame for limited rocking movement in a plane parallel to the longitudinal axis of said frame, and grate bars supported at their ends by said units.

3. A grate comprising the combination of,

a frame, a plurality of fuel-supporting units in a row lengthwise of said frame and mounted for limited rocking movement in a plane parallel to the longitudinal axis of saidfranic, each unit having a trunnionsocket and grate bars having trunnions received in said sockets. j

4. A grate comprising the combination of a frame, fuel-supporting units mounted on said frame for limited rocking movement in a plane parallel to thelongitudinal axis of said frame and provided with means for supplying air to fuel supported thereon, and grate bars supported at their ends by said units. j

5. A grate comprising the combination of a frame, fuel-supporting units mounted on said frame forlimited rocking movement in a plane parallel to the longitudinal axis of rsaidframe, said units being provided with 5 constituting a fuel-supporting surface, said means defining vertical passages for upward flow of air to fuel supported thereon, and

grate bars supported at their ends by said units. Y

6. A grate COIHPIlSlIlg'tllQ combination of a frame, fuel-supporting units mounted in a row on said frame for limited rocking movement in .a plane parallel to the longitudinal axis of said frame, .each unit having a multiplicity of spaced projections, each projections being separated by air channels and grate bars supported at their ends by said units.

7 A grate comprising the combination of a frame, fuel-supporting units mounted on said frame for limited rocking movement in a plane parallel to the longitudinal axis of said frame, said units being removable from said frame, and grate bars supported at their ends by said units. V

8. A grate frame which comprises a main frame member, fuel-supporting units mounted on said member and having a limited freedom of rocking movement relative to said member in a plane parallel to the longitudinal axis of said member, said units being provided with means for supplying air to fuel carried thereby including vertical air passages along the faces of the units.

9. A grate frame which comprises a main frame member having a plurality of mountings thereon, and fuel-supporting units on said mountings, each unit having a recess in which a part of a mounting is loosely re ceived, the loose fit permitting the unit to rock on its mounting to a limited degree in the plane of the frame.

10. A grate frame comprising a main frame member having upstanding projec- 12. A grate frame which comprises a main.

frame member having a plurality of projections thereon, and a fuel-supporting unit on each projection, said unit fitting its projection loosely and having a limited freedom of movement relative to said projection, and

said unit and projection having cooperating parts adapted uponsaid relative movement to lock said unit and projection together.

13. A grate frame comprising a main frame member having a row of spaced projections along its top, and fuel-supporting units mounted on said projections and removable therefrom, each unit having a recess in its lower edge in which a projection is loosely received and having an open-top re-.

cess in its upper surface for receiving the trunnion of a grate bar.

In testimony whereof Iaffix my signature.

JAMES, s. THOMPSON. 

